Field of the Invention
The present invention relates to an electroacoustic converter that can be applied to earphones, headphones, mobile information terminals, etc., for example.
Description of the Related Art
Piezoelectric sounding elements are widely used as simple means for electroacoustic conversion, where popular applications include earphones, headphones, and other acoustic devices as well as speakers for mobile information terminals, etc. Piezoelectric sounding elements are typically constituted by a vibration plate and a piezoelectric element attached on one side or two sides of the plate (refer to Patent Literature 1, for example).
On the other hand, Patent Literature 2 describes headphones equipped with a dynamic driver and a piezoelectric driver, where these two drivers are driven in parallel to allow for wide playback bandwidths. The piezoelectric driver is provided at the center of the interior surface of a front cover that blocks off the front side of the dynamic driver and functions as a vibration plate, so that constitutionally this piezoelectric driver can function as a high-pitch sound driver.